SOLUTION: This problem is not from a textbook. Solve the system. X2+y2=145 X+y=17 The answer choices are (9,8) (8,9) (-9,-8) (-8,-9) (-9,8) (-8,9) (9,-8) (8,-9)

Algebra ->  Rational-functions -> SOLUTION: This problem is not from a textbook. Solve the system. X2+y2=145 X+y=17 The answer choices are (9,8) (8,9) (-9,-8) (-8,-9) (-9,8) (-8,9) (9,-8) (8,-9)       Log On


   

Question 134573: This problem is not from a textbook. Solve the system.
X2+y2=145
X+y=17
The answer choices are
(9,8) (8,9)
(-9,-8) (-8,-9)
(-9,8) (-8,9)
(9,-8) (8,-9)
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
X2+y2=145
X+y=17
The answer choices are
(9,8) (8,9)
(-9,-8) (-8,-9)
(-9,8) (-8,9)
(9,-8) (8,-9)
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x = 17-y
Substitute to get:
(17-y)+y^2 = 145
17^2-34y+2y^2 = 145
2y^2-34y+144 = 0
y = [34 +- sqrt(34^2-4*2*144)]/4
y = [34 +- sqrt(4)]/4
y = [34 +- 2]/4
y = 9 or 8
If y = 9, x = 8
If y = 8, x = 9
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